title: Ethers and esters derived from apocynin avoid the interaction between p47phox and p22phox subunits of NADPH oxidase: evaluation in vitro and in silico.
abstract: NOX (NADPH oxidase) plays an important role during several pathologies because it produces the superoxide anion (O2•-), which reacts with NO (nitric oxide), diminishing its vasodilator effect. Although different isoforms of NOX are expressed in ECs (endothelial cells) of blood vessels, the NOX2 isoform has been considered the principal therapeutic target for vascular diseases because it can be up-regulated by inhibiting the interaction between its p47phox (cytosolic protein) and p22phox (transmembrane protein) subunits. In this research, two ethers, 4-(4-acetyl-2-methoxy-phenoxy)-acetic acid (1) and 4-(4-acetyl-2-methoxy-phenoxy)-butyric acid (2) and two esters, pentanedioic acid mono-(4-acetyl-2-methoxy-phenyl) ester (3) and heptanedioic acid mono-(4-acetyl-2-methoxy-phenyl) ester (4), which are apocynin derivatives were designed, synthesized and evaluated as NOX inhibitors by quantifying O2•- production using EPR (electron paramagnetic resonance) measurements. In addition, the antioxidant activity of apocynin and its derivatives were determined. A docking study was used to identify the interactions between the NOX2's p47phox subunit and apocynin or its derivatives. The results showed that all of the compounds exhibit inhibitory activity on NOX, being 4 the best derivative. However, neither apocynin nor its derivatives were free radical scavengers. On the other hand, the in silico studies demonstrated that the apocynin and its derivatives were recognized by the polybasic SH3A and SH3B domains, which are regions of p47phox that interact with p22phox. Therefore this experimental and theoretical study suggests that compound 4 could prevent the formation of the complex between p47phox and p22phox without needing to be activated by MPO (myeloperoxidase), this being an advantage over apocynin.
authors.affiliation: Laboratorio de Biofísica y Biocatálisis, Sección de Estudios de Posgrado e Investigación de la Escuela Superior de Medicina del Instituto Politécnico Nacional, México.
authors.forename: Martha Edith
authors.initials: ME
authors.lastname: Macías-Pérez
authors.forename: Federico
authors.initials: F
authors.lastname: Martínez-Ramos
authors.forename: Itzia Irene
authors.initials: II
authors.lastname: Padilla-Martínez
authors.forename: José
authors.initials: J
authors.lastname: Correa-Basurto
authors.forename: Lowell
authors.initials: L
authors.lastname: Kispert
authors.forename: Jessica Elena
authors.initials: JE
authors.lastname: Mendieta-Wejebe
authors.forename: Martha Cecilia
authors.initials: MC
authors.lastname: Rosales-Hernández
mesh_terms: D000098:Acetophenones / Q000737:chemistry* / Q000494:pharmacology; D001665:Binding Sites; D001713:Biphenyl Compounds / Q000737:chemistry; D004952:Esters; D004987:Ethers / Q000737:chemistry / Q000494:pharmacology; D016166:Free Radical Scavengers / Q000737:chemistry* / Q000494:pharmacology; D057809:HEK293 Cells; D006801:Humans; D062105:Molecular Docking Simulation; D019255:NADPH Oxidases / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000378:metabolism; D010851:Picrates / Q000737:chemistry; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D017433:Protein Structure, Secondary; D021122:Protein Subunits / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D013481:Superoxides / Q000737:chemistry
chemical_list: D000098:Acetophenones; D001713:Biphenyl Compounds; D004952:Esters; D004987:Ethers; D016166:Free Radical Scavengers; D010851:Picrates; D021122:Protein Subunits; D013481:Superoxides; C056165:acetovanillone; C004931:1,1-diphenyl-2-picrylhydrazyl; D019255:NADPH Oxidases; C086986:CYBA protein, human; C060505:neutrophil cytosolic factor 1